Blowpipe.



A. KOFUD'.

BLOWPIPE. APPLIGATION FILED JUNE 22, 1912.

Patented Jan. I9, 1915.

characters on TEE sTATEs PATEN, Eric.

AAGE Kore-p, 0E ZURICH, sWITzEELAND, AssIGNoE, EY MEsNE ASSIGNMENTS, To

LIQUID FUEL 6c GAS COMPANY, OF OF WEST VIRGINIA. i

To all whom 'it may concern Be it known that I, AAGE KoFoD, a subject of the King of Denmark, residing at Zurich, in Switzerland, have invented an Improvement in Blowpipes, of which the following description, in connection' with the accompanying drawing, is a specification, like the drawing representing like parts. A l

This invention relates to lblow pipes for heating vor welding lmetal of that type in which the heat isf developed by burning a mixture of hydrocarbon gas and oxygen. The temperature of the flame produced by hydrocarbon gas and oxygen when used under ordinary pressures is such that when the metal to be melted is comparatively thick it is necessary to play for a considerable length of time in order to bringit to the melting point, and unless great vcare is exercised, the metal isapt to be burned before the welding process is completed, with the result that the [weld will be more or less defective. An increased temperature can be produced with these gases by increasing the pressure or the velocity of the gas mixture as it is delivered from the mouth piece of the blow pipe, but when the higher pressure and consequent increased velocity of the gasl mixture as it is delivered is used the gases areliable to be imperfectly mixed, thus producing imperfect combustion.

v,oxidizin Moreover, if the oxygen gas is/not completely consumed' it has an undesirable elect on` the hot metal. i

The o jectlof the present invention' is to provide a" blowV pipe which canbe successfully used Ywith the' hydrocarbon-oxygen flame without the disadvantages above enu- 'lng merated,fand c,Iaccomplish vthis 'result by providing a tip or mouth piece for the blow pipe which is `vformed withla central inlet passage into 'which'the mixed gases are delivered and with an annular expansion champassage and ber that surrounds said inlet communicates therewith throughy throttling ports soA that the mixed gas is throttled or the pressure thereof is 'reduced as it Hows into the expansion chamber, and which is also formed with a circular discharge opencommunicating with the expansion chamber and through which the throttled gases pass, said gases beingfburned as they a'I-:.rlcliveredr from Said -circular opening.

.Myfinvention-'niay be' embodied in a va- Specication of Letters Iatent. Application led June 22, 1912. Serial Noz 705,168.

the flame on the metal.

pipe apparatus BLOWPIPE.

Patented Jan. 19, 1915.

riety of constructions, some ofwhich I have illustrated in the accompanying drawings.

Figurel is a vertical cross sectional view of a blow pipe tip or mouth piece embodying my invention. Fig. 2 is a section on the line .o3-m, Fig. 1; Fig'B is a view similar to Fig. t

1 showing another embodiment of the invention., Fig. 4 is an end viewvof Fig. 3; Fig.

5 is a view similar to Fig. 1 showing another 4embodiment of the invention. Fig. 6 is a section on the line g/g/', Fig. 5; Fig. 7 is a view similar to Fig. 1 showing another embodiment of the invention. Fig. 8-is an end view of Fig. 7. Fig. 9 is a view similar to Fig. 1 showing another embodiment of the invention. Fig. 10 is en -a., Fig. 9; Fig. 11 is a view similar to Fig. 1 showing another embodiment'of the invention.4 Fig. 12 is a sectionson the line b-n Fig. 11; Fig. 13 is an end view of the tip showing a slightly different construction from that shown in the other figures.

1 designates a delivery pipe of the blow 4to which my improved burner or tip is attached, said pipe leading from a suitable gas-mixing apparatus, not shown, which may be formed in or carried by a suitable handle. My improved tip or mouthpiece is formed with thefcentral -inlet passage into which the `mixed gases are delivered from the pipe 1 "and an yannular expansion chamber which surrounds the inlet passage and communicates therewith sure of the gas is reducedras it passes into the expansion chamber. My improved tip is also made with an annular discharge opening which communicates' with the expansion chamber and terminates at the end of the ti repsult that the mixed gases are delivered from the expansion chamber in a ring which produces a circular flame.

In the embodiment shown in Fig. 1 the inlet passage is shown at 2, the expansion chamber is shown at 3, the throttling ports through which the gas 1is delivered to the expansion chamber are shown at 4,v and the annular discharge opening is shown at 5. A tip or burner having these features may be made in various ways. In the construction shown in Fig. 1 the tip or mouth piece comprises a tubular member '7 which is adapted to screw onto the screw-threaded end' 8 of the pipe 1 and is provided with a a section on the line` in an annular burner opening with they WHEELING, WEST VIRGINIA, A CORPORATION.

a central bore which forms the inlet pas-- sage 2. The interior member 10 is formed with the extension 13 which enters the portion 15 of the bore in the exterior member 7, said extension having such a-diameter rela.- tive' to the portion 15 of the bore' as to leave the annular discharge opening. 5. The throttling ports 4 are formed in the interior member and are preferably situated so as to enter the expansion chamber near the upper end thereof. With this constructionl the mixed gases under pressure enter the inlet passage 2` and thence pass through the throttling ports 4 into the expansionl chamber 3. The relation between the ports 4 and the expansion chamber 3 is such that the gases are' delivered to the chamber at a reduced pressure' and expand in' said chamber, and these expanded gases pass out through thev annular discharge port 5' which terminates at the end 6 of the tip in an annular burner opening; The result of this construction is that a circular fiame is produced which I have found will generate a suflicient temperature to melt metal without danger of burning it or otherwise injuring it.

In Figs. 3 and 4 I have shown an embodiment of'my invention wherein mea-ns are -provided for delivering a single jet of mixed gas under high pressure through the end of the tip centrally of the circulai` flame. I accomplish this result by providing the interior member 10 with a central port 16 whichcommunicates with the inlet passage 2 and terminates at the end 6 of the tip. When a tip of this sort is used a jet of gas mixture under high pressure will be delivered from the central bore 16 at a much higher velocity than the annular stream of gas which is delivered through the discharge opening 5. F or some purposes this form of tip is preferable to that shown in Figs. 1 and 2.

In Figs. 5 and 6 I have illustrated another embodiment of mv invention in which the expansion chamber 3a is of uniform size throughout its length and is also of the same cross sectional area as the discharge passage 5a. There will, therefore, be no throttling effect between the expansion chamber and the discharge passage. In this embodiment also the central bore 16 is enlarged at its end, as shown at 17., so that the gases under high pressurewhich are delivered from the inlet passage 2 will expand in the enlarged chamber 17 and will be burned under a reduced pressure.

In Figs. 7 and 8 I have shown an embodiment of the invention wherein the discharge opening 5b is frusto-couical in shape, this being secured b v making the end of the central member 10b with the conical portion 18 and giving the bore of the exterior member 7b a. conical shape at its end. In this embodiment of the invention I have shown the central discharge passage 16b which delivers the gas under high pressure centrally7 ofthe annular flame.

In Figs. 9 and 10 I have shown an embodiment of the invention wherein the end of the: central member 10c is situated a. slight distance back from the end 6 of the tip so that' the exterior member projects be- `vond the end of the annular discharge opening 5. In this embodiment I have shown the central-'discharge passage 16, the end of which is enlarged at 17C. This construction "results in a comparatively wealrelongated flame.

In Figs. 11 and 12 I have shown a. con` struction which 4is especially advantageous for welding sheet metal of considerable thickness. In this embodiment I have shown the tip as provided. withtwo concentric annular discharge openings as well as a central discharge opening.` Said tip or mouth piece comprises the exterior cylindrical member 7d having a central bore of uniform diameter which receives a cylindricall member 19 which is smaller than said bore thereby to form the annular expansion chamber 3d which leads to and communicates with the annular discharge opening 5d. rIhis member 19 has the inlet assage 2d and the throttling ports 4 throng which the gas mixture passes to the expansion chamber 3d. The member 19 is provided with a central bore in which is received an inner member 10d of such a size that an annular space 20 is formed between said inner member and the member 19. This inner member 10d is provided with a central passage 21 Which communicates with the .annular space 20 through the throttling erts 22, and said member is preferably aso provided with a central discharge port 16a through which gas mixture under hi her pressure is delivered through the en 6 'of the tip. With this construction the gas flames is a third flame of the gas burningl under a higher pressure.

In the embodiments of the invention shown in Figs. 3, 4, 7, 8, 11 and 12 the ame issuing .from the central passage is some- IIE macea what elongated relative to the circular,

flame, and in all of these constructions the iame produced will be an. annular or circu- 'lar flame having an elongated central portion.

I have found that with a tip embodying my inventionv as above described it is possible to successfully use a gas mixture formed of hydrocarbon gas and oxygen without danger of burning the metal.

While I have herein shown the discharge opening as a continuous annular opening, yet it will be obvious that the same effect could be secured by making said opening in the form of a circular row of apertures 5e, as shown in Fig. 1.3. These lapertures are shown as drilled in the exterior Amember 6 and are formed te extend from the tip of' the member 6 to the expansion chamber.

G Having fully described my invention, what I claimY as new and desire to secure by Letters Patent is :-y

1. In a mouth piece for a blow pipe, the

r K combination with an exterior member having a central bore extending entirely therethrough, of an inner. member situated within said exterior member and having a diameter smallenfthan that of the bore to provide an annular expansion chamber between said 3 members, the inner end of the inner member being secured to the exterior member, 'said .inner and outer members providing between them a circular discharge' opening which communicates with the expansion chamber and through which the gas producing the working flame is delivered, said inner member having a central inlet passage and throttling ports connecting said passage with the expansion chamber.

2. In a mouth piece for a blow pipe, the

`combination with an exterior member havbetween them a circular discharge opening which communicates with the expansion chamber and through which the gas producing the working flame-is delivered, said inner member having a central, inlet passage and throttling ports connecting said passage with the expansion chamber.

In testimonyV whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

AAGE KOFOD.

Witnesses CARL CUBLE, AUGUST RUEGG. 

